Band stresser



R. P. SNYDER BAND STRESSER Nov. 13, 1962 Filed Jan. 17, 1961 Nov. 13, 1962 R, P, SNYDER 3,063,677

BAND STRESSER Filed Jan. 17, 1961 2 sheets-sheet 2 United States Patent 'O Walker Refractories Company, a corporation of Penn- Sylvania Filed Jan. 17, 1961, ser. No. 83,261 s claims. (ci. 2s4-s1) This application relates to lapparatus for tightening or stressing metal bands, and more particularly to stressers oper-ated by iluid pressure.

Band tighteners, especially for binding boxes, are old and well known. However, few, if any, of such tighteners are capable of ltightening heavy meta-l bands that may be several inches wide and a half inch thick. Such bands are used, for example, around settling tanks and thickening tanks made of concrete or ceramic blocks and having diameters ranging from 150 to 320 feet. The pressure of the tank walls against the encircling retaining bands `is sometimes higher than 10,000 pounds per square inch. Ordinary band tighteners are completely inadequate for pulling heavy metal bands tightly around such tanks.

It is among the objects of this invention to prov-ide a lband stresser which is capable of exerting very great tension on a heavy metal band, 'which is simple in construction and operation, which is adjustable, and which can easily be separated into a number of parts for portability.

In accordance with this invention a pair of laterally spaced parallel bars have rigid connecting members mounted on their opposite ends and spanning the space between them. Means are provided for holding the connecting members stationary on the bars. Slidable lengthwise of the bars between the connecting members is a crosshead, between which end one of the connecting members uid pressure means are disposed for moving the crosshead toward the other connecting member. The latter and the crosshead are formed for pushing toward each other a pair of connectors between them, which are secured to the ends of a metal band extending around an object so that the band can be tightened. lOne of the connectin-g members may be adjusted along the bars and, along with the crosshead and the other connect-ing member, be removable from the bars for carrying.

The preferred embodiment of the invention is illustrated in the accompanying drawings, in Iwhich FIG. 1 is a plan view of the apparatus in operative position;

FIG. 2 is a side view thereof;

FIG. 3 is an enlarged fragmentary longitudinal section taken on the line III-III of FIG. 1, but before the band has Ibeen fully tightened;

FIGS. 4 and 5 are enlarged end views of the apparatus along the lines IV-IV and V-V, respectively, of FIG. 2; and

FIG. 6 is an enlarged cross section taken on the line VI-VI of FIG. 2.

Referring to FIGS. 1, 2 and 4 of the drawings, a pair of parallel bars 1 are spaced apa-rt by connecting members 2 and 3 at their opposite ends. Preferably, each connecting member is slidably mounted on the bars, but it is held in fixed position thereon during use. The front connecting member 2 may be formed from two channelshaped shoes 4 that dit down over the bars and have their open lower sides closed by a cross member, such as a at plate 5, welded to the shoes. The shoes and plate form sleeves that receive the ends of the bars. Each shoe has aligned transverse openings 6 through it, which can be aligned with any one of a series of longitudinally spaced passages 7 through the adjoining end portion of a bar. To hold the connecting member in any desired position ICC 2 along the bars, removable pins 8 are inserted in openings 6 and the bar passages aligned with them. To hold the pins in place, it is preferred that a short sleeve 9 be welded to the outer side of each shoe around the transverse open ing therein and be provided with radial holes, with which a hole through the pin can be aligned for reception of a cotter key 10, nail, or the like. f

The connecting member 3 at the rear ends of the bars is formed in the same general way. As shown in FIGS. 1, 2 and 5, it has shoes 11 connected by a metal base plate 12 that spans the space between them. The bars are provided -with only one set of passages 13 for receiving locking pins 14 extending through sleeves 15 Welded to the shoes around lateral openings 16 in the shoes. This connecting member has an upright front plate 17 perpendicular to the base plate and welded thereto and to the shoes. Carrying handles 18 may be welded to the front plate and the shoes.

Between the two connecting members 2 and 3, a crosshead 19 is slidably mounted on the two bars. It is formed similarly to the second connecting member, from shoes 20 fitting over the bars and connected by a `base plate 2f1 and an upright plate 22 welded to them. Handles 23 may be secured to the upright plate and the shoes for carrying the apparatus, or setting it in operative position.

For moving the crosshead 19 toward the front ends of the bars, fluid pressure means are mounted between it and rear connecting member 3. Perferably, such means include two hydraulic rams, the cylinders 25 of which have threaded studs 26 at their rear ends extending through upright plate 17, where they; are clamped by threaded collars 27. The front ends of the ram pistons 28 are held against the back side of upright plate 22 of the crosshead Iby cap screws `29 extending through it. T-he rear ends of the two cylinders are connected by Va pipe 31 that has a T-tting 32 connected by a flexible tube 33 with a manually operable pump 34. A pressure gauge 35 ,is connected to the fluid pressure line so that the operator will know how much pressure is being applied to the rams and consequently the tension on the metal band.

This apparatus is intended to be placed upon or against the end portions of a metal strap or band 40 extending lengthwise of the bars and `around an object, such as a large settling tank, around which the band is to be tightened and fastened. The band may, for example, be ouehalf inch thick and several inches wide. The -base plates 5, 12, and 2x1 of the apparatus engage the band, and a pair of connectors 41, that have previously been secured to the ends of the band, are disposed between crosshead 19 and the front connecting member 2. The crosshead then is moved ahead by the rams to cause it and the front connecting number to engage the two connectors. The opposed edges of base plates 5 and 21 preferably are provided with notches 412 and 43 to center the connectors between the side bars. In case the crosshead would have to be moved too far to engage a connector, pins 8 are first removed from the front connecting member 2 and then it is slid back on the bars and the pins replaced. When everything is ready, more lluid is pumped into the ram cylinders to force lthe crosshead toward the front connecting member whereby the two band connectors will be pushed toward each other as shown in FIGS. l and 2 to draw the band tightly around the object it surrounds. When the band has lbeen tightened the desired amount in this manner, the two connectors are fastened together and then the stresser can be removed.

Although the connectors and the means for fastening them together may take various forms, it is preferred to make each of the connectors from a pair 0f spaced parallel plates 45 welded to an end portion of the band and connected at one end by a transverse plate 46 projecting from the band. Welded between the opposite ends of the parallel plates some distance from the band is a block 47. The end plates 46 have openings 48 through them, through which extends a heavy bolt 49 that is located between the band and the blocks. Nuts 50 and washers 51 are mounted on the opposite ends of the bolt. After the band stresser has tightened the band as much as desired, the nuts 50 are tightened by a wrench against the connectors to hold the band tight when the stresser is removed. As shown in FIG. 3, connector blocks 47 preferably are tilted slightly forward and toward the band so that as the bolt is tightened and they engage flat against it they lift the ends of the strap and prevent them from digging into the object surrounded by the strap.

The band stresser described herein can be dismantled easily for storage or carrying to another location. All lthat is necessary to do is to disconnect fluid line 33 from tting 32, remove locking pins 8 and 14 and cap screws 29, and then pull bars 1 out of the crosshead and the end connecting members. If desired, the rams can also be disconnected from rear connecting member 3. The result is a number of small, light-weight parts.

According to the provisions of the patent statutes, I have explained the principle of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specically illustrated and described.

I claim:

l. Apparatus for stressing a metal band extending around an object and having connectors secured to its ends, said apparatus comprising a pair of laterally spaced parallel bars, a pair of shoes mounted on the bars at each end Vof the apparatus, at least one of said pair of shoes being slidably mounted, a cross member rigidly connecting each pair of shoes, means for adjusting the shoes along the bars, a crosshead having shoes slidably mounted on the central portion of the bars, and fluid pressure means disposed between one of said cross members and the crosshead for moving the latter toward the other cross member, said other cross member and the crosshead beingpforrned for pushing toward each other a pair of band connectors disposed between them.

2. Apparatus for stressing a metal band extending around an object and having connectors secured to its ends, said apparatus comprising a pair of laterally spaced parallel bars, a pair` of shoes mounted on the bars at each end of the apparatus, at least one of said pair of shoes being slidably mounted, a cross member rigidly connecting each pair of shoes, each shoe being provided with a lateral opening, a sleeve secured to the shoe around said opening and projecting therefrom, said bars being provided with transverse openings aligned with said sleeves, a removable pin in each sleeve projecting into a bar opening to lock the shoe on the bar, means for locking the pins in the sleeves, a crosshead mounted on the central portion of the bars and slidable along them, and uid pressure means disposed between one of said cross members and the crosshead for moving the latter toward the othercross'member, said other cross member and the crosshead being formed for pushing toward each other a pair of band connectors disposed between them.

3. In combinationwith a metal band adapted to extend around an object and having its ends near each other, a pair of spaced side plates welded to each end portion of the band land projecting outward therefrom, an end plate connected to each pair of side plates at the end thereof farthest from the adjacent end of the band, said end plates beingv provided with aligned bolt-receiving openings therethrough, a pair of laterally spaced parallel bars extending along the opposite edges of said end portions of the band, rigid connecting members mounted on the opposite ends of the bars and spanning the space between them, a crosshead mounted on the bars between said members and slidable lengthwise of the bars, said members and crosshead engaging the outer side of the band, the opposed edges of one of said members and the crosshead having notches therein receiving said end plates, Huid pressuremeans disposed between the other of said members and the crosshead for moving the latter toward said one connecting member to push the end plates toward each other, and blocks welded between each pair of side plates at the end opposite the associated end plate, said blocks being tilted toward each other and positioned to bear against the outer side of a tie bolt inserted in said plate openings, whereby the extreme ends of the band will be forced by the bolt outward away from said object.

References Cited in the le of `this patent UNITED STATES PATENTS 1,560,091 Nygren Nov. 30, 1925 A2,100,564 Mandl Nov. 30, 1937 2,612,802 Y McAneny Oct. 7, 1952 2,724,201 Cavalero Nov. 22, 1955 

